Meningococcal carriage: prevalence and sex-related risk factors.

A retrospective analysis was done to examine whether sexual behaviour was associated with meningococcal carriage. Over the 4 month period from January to April 1994, 136 (27.4%) of the 496 consecutive new/re-registered genito-urinary medicine clinic attenders showed meningococcal carriage. Two (15.4%) of 13 homosexual men compared with 134 (27.7%) of 484 heterosexual men and women had evidence of meningococcal carriage. Relative risk (RR) of meningococcal carriage was 1.8 with > 10 lifetime partners and 1.2 with 3-10 partners (P < 0.007). RR with age group of 16-25 was 4.2 and for 26-35 it was 3.5. There was no relationship with meningococcal carriage and pharyngeal symptoms, sexual orientation, intravenous drug use, number of partners per month and orogenital sex. Further longitudinal studies may be of value in order to determine whether a high number of sexual partners is a marker for meningococcal carriage. In addition, further study may show whether there is an increased risk of meningococcal carriage and disease in those who live with meningococcal carriers.